A. Field of the Invention
The present invention relates generally to the communications field, and, more particularly to a module for holding printed circuit boards (PCB) used in the communications field.
B. Description of the Related Art
Printed circuit board (PCB) assemblies are used in computers, communications equipment, televisions, and many other products. In a typical PCB assembly, many electrical components are attached to the top and bottom surfaces of a PCB. Since the electronics manufacturing industry is highly competitive, it is important to maximize the throughput of processing PCB assemblies and to securely attach functional electrical components to the PCBs.
The manufacturing of PCB assemblies involves many processes, one of which is surface mounting components to PCBs. In addition to maximizing the throughput of processing PCB assemblies, it is also becoming important to accurately mount a large number of very small components to one side of the PCB assemblies. Once the PCB is completed, tests need to be performed upon the PCB to ensure its functionality and validate the PCB. Furthermore, tests need to be performed when PCBs fail in the field.
When components are mounted onto a PCB or a PCB is tested, the PCB is typically mounted in a fixture that holds the PCB. Conventional PCB fixtures hold a single PCB in a horizontal plane so that one side of the PCB may be processed or tested. Typically, the PCB is soldered to conventional connections provided on conventional fixtures. After the PCB is soldered and tested, it is difficult to remove the PCB from the soldered connections without damaging or destroying the PCB. Thus, it is essential that PCBs be easily removed from a fixture, without damaging or destroying the PCB.
When a PCB is being tested, it must be removed from its assembly in which it normally operates. Typical PCB assemblies include walls and mechanisms for cooling the PCBs contained therein, such as heatsinks and fans. Unfortunately, when PCBs are removed from their assemblies and are electrically connected for testing purposes, the heat generated by the PCB is not sufficiently dissipated which increases the PCB temperature significantly. In other words, conventional PCB fixtures fail to provide a mechanism to cool the PCB as it is being tested outside the assembly in which it normally operates. The increased heat may damage the PCB, adding significant costs for replacement or repair of the damaged PCB. The heat may also create latent defects in the PCB that do not surface until after the PCB is in operation. Moreover, some PCBs have a narrow operating range such that significant deviations in temperature will affect the performance of the PCB and may lead to inaccurate testing results.
Therefore, there is a significant need in the art to quickly, consistently, and temporarily support PCB assemblies with different configurations of components in the manufacturing and testing of PCB assemblies. There is also a need in the art for a PCB fixture that does not damage the PCB upon removal therefrom, and provides a mechanism to dissipate heat from the PCB being tested at the same rate as if the PCB were installed in an assembly in which the PCB normally operates.
The present invention solves the problems of the related art by providing a module that holds a PCB for processing, testing, and validating, and which provides mechanisms for cooling the PCB as it is being processed or tested.
As embodied and described herein, the present invention is broadly drawn to a module for holding a printed circuit board (PCB) that includes mating top and bottom brackets. The top bracket has four walls, and the bottom bracket slidably receives and retains the printed circuit board. At least one wall of the top or bottom brackets retains an electrical connector having a lead. The module further includes a dielectric gasket provided on one side of the electrical connector lead. A portion of a connection force provided by the top and bottom brackets sandwiching the electrical connector lead and the dielectric gasket, is transferred through the dielectric gasket to the electrical connector lead, and electrically connects the electrical connector lead with a pad of the PCB.
In a specific embodiment, the invention three walls of the top bracket retain SMA connectors that interconnect with the PCB. A dielectric gasket is provided below each SMA connector to apply pressure on the leads thereof so that the leads adequately contact corresponding pads on the PCB. Two walls of the bottom bracket include channels that slidably receive and retain the PCB therein, and another wall includes a stop channel that retains an edge portion of the PCB when the PCB is slid through the channels. The bottom bracket also has diamond-shaped pads and a square-shaped pad, connected between two walls thereof, that align with and support corresponding components provided on the PCB and dissipate heat generated thereby. A cable connector provided on one end of an electrical cable connects to each SMA connector, and the other ends of the electrical cables connect to testing equipment. Thus, when the top bracket is connected to the bottom bracket, the dielectric gaskets provide pressure on SMA connector leads so that the leads electrically contact corresponding pads on the PCB and enable the PCB to be tested without being permanently affixed to the module. The module may be attached to a heatsink that, in conjunction with the diamond-shaped pads and the square-shaped pad, permits heat to be dissipated from the PCB at the same rate that heat is dissipated from an installed PCB.